by gum!
US /baɪ ɡʌm/
UK /baɪ ɡʌm/

1.
parbleu, sacrebleu
an exclamation of surprise or emphasis
:
•
By gum, that's a big fish!
Parbleu, c'est un gros poisson !
•
Well, by gum, I never thought I'd see the day!
Eh bien, parbleu, je n'aurais jamais cru voir ce jour !